E-beam deposition systems use a focused beam of electrons to heat a small area of material to be evaporated in a crucible. Currents in x and y electromagnetic coils are varied to steer the electron beam and to modulate the position it strikes the surface of the material in the crucible (referred to as the “melt surface” even if a solid material in the crucible sublimates). Continuous scanning of the melt surface by the electron beam is used to evenly heat the melt surface and thus uniformly deplete the feedstock material as it evaporates.